Polyglycidol sulfated surfactants having antimicrobial activity

ABSTRACT

The present invention relates to novel compounds represented by the formula: ##STR1## wherein R is an alkyl group having from about 8 to about 18 carbon atoms, and mixtures thereof, n has a value from 1 to 6, R 1  is selected from the group consisting of an alkyl group having from 1 to about 12 carbon atoms, H, or ##STR2## wherein the sum of n-m=3 to 12, Z═H or SO 3  M and M═NH 4 , Na, or K. These compounds possess antimicrobial activity and are useful as cleaning agents and preservatives, particularly in water-base functional fluids and surface coating compositions.

This application is a continuation-in-part of U.S. patent applicationSer. No. 07/590,998, filed Oct. 1, 1990, now abandoned.

FIELD OF THE INVENTION

The invention relates generally to novel compounds having antimicrobialactivity, and more particularly to polyglycidol sulfated surfactants andtheir use in cleaning compositions.

BACKGROUND OF THE INVENTION

General purpose or all-purpose household cleaning compositions for hardsurfaces such as metal, glass, ceramic, plastic and linoleum surfacesare sold commercially in both powdered and liquid form. The powderedcompositions consist mainly of builders and buffering salts such asphosphates, carbonates, silicates and the like and these compositionsare diluted with water prior to use. While use concentrations of suchcompositions usually provide good inorganic soil removal, they tend tobe deficient in removal of organic soils such as the greasy/fatty/oilysoils typically found in the domestic environment. Further, suchcompositions tend not to be compatible with germicidal ingredientsbecause of the presence of anionic detergents and high concentrations ofbuilder salts.

On the other hand, all-purpose liquid cleaners have met with greatercommercial acceptance because they have the advantage that they can beapplied to hard surfaces in neat or concentrated form so that arelatively high level of surfactant material is delivered directly tothe soils. Because of these advantages, much research and developmenteffort has been expended on formulating all-purpose liquid cleaningcompositions which are stable upon storage, have good physicalproperties and are effective in removing inorganic and organic soils.

Liquid hard surface cleaners generally have been classified into twotypes. The first type is a particulate aqueous suspension havingwater-soluble abrasive particles suspended therein, which particles arepalpable. Some of the cleaners of this type suffer a stability problemand other cleaners of this type have received poor acceptance byconsumers because of their "gritty" feel which causes many people to bereluctant to use then for fear of scratching the surface to be cleaned.The second type is the liquid detergent without suspended abrasive and,seemingly, this latter type is preferred by consumers. While this secondtype generally is a mixture of surfactant and builder salt in an aqueousmedium, the product formulations in the market place have varied widelyin composition.

One liquid product which achieved some success was based upon a mixtureof soap, alkylbenzene sulfonate and fatty acid alkanolamide plusinorganic builder salts. This liquid product exhibited good temperaturestability and a desirable viscosity, but tended to exhibit cleaningdisadvantages when compared with another product based upon a mixture ofalkylbenzene sulfonate and ethoxylated alkanol plus builder salts.However, the latter composition usually required a high concentration ofa lower alkylbenzene sulfonate hydrotrope in order to achievehomogeneity in the presence of builder salt and the inclusion ofhydrotrope resulted in lower viscosity and the need of thickeningagents.

Other all-purpose liquid products have been prepared which incorporate asolvent such as a terpene. For example, German patent application No.2,113,732 discloses the use of terpenes as antimicrobial agents inwashing compositions. British patent no. 1,308,190 teaches the use ofdipentenes in a thixotropic liquid detergent suspension basedcomposition. German patent application No. 2,709,690 teaches the use ofpine oil, a mixture of largely terpene alcohols, in liquid hard surfacecleaning compositions. U.S. Pat. No. 4,414,128 teaches the use ofterpenes with solvents of limited water solubility such as benzylalcohol in all-purpose cleaning compositions. The terpenes are used toprovide cleaning as well as to control sudsing. A similar composition isdisclosed in European patent application No. 0080749 which comprisessurfactant terpenes, butyl carbitol and builder salts. Again, theterpenes are included for cleaning and as suds regulators.

U.S. Pat. No. 4,272,395 describes a high foaming detergent compositionsuitable for use in dishwashing and in the cleaning and disinfecting ofhard surfaces obtained by combing a quaternary ammonium compound havinga formula: ##STR3## wherein R₁ and R₂ are alkyl groups each having 9 to11 carbon atoms, R₃ and R₄ can each be an alkyl group, an alkylethergroup or a hydroxyalkyl group having 1-3 carbon atoms, or a benzylgroup; and X⁻ is either Cl⁻, Br⁻, I⁻, NO₃ ⁻, 1/2 SO₄ ²⁻, CH₃ SO₄ ⁻, C₂H₅ SO₄ ⁻, 1/2 HPO₄ ²⁻, or CH₃ COO⁻, and a co-surfactant selected fromthe group consisting of short chain anionic surfactants having 3-8carbon atoms in the hydrophobic groups, low alkoxylated nonionicsurfactants having 0-4 ethylene oxide and/or propylene oxide groups inthe molecule, and mixtures thereof.

Despite the extensive efforts in formulating all-purpose liquid cleaningcompositions, there is still a need for a liquid product with botheffective cleaning properties and disinfecting properties when appliedneat, as well as at various concentrations when used in water. Also suchproducts should be effective at varying water hardness levels, shouldhave desirable foaming characteristics, and should cause little or nospots or streaks in the presence or absence of rinsing. Further, theresultant product should be homogeneous at temperatures from about 5° C.to about 49° C. and should exhibit a desirable viscosity. In addition,such a product cannot be achieved by simply adding a germicidalquaternary ammonium compound to one of the liquid products discussedabove because the quaternary compounds are rendered ineffective by theproportions of anionic detergent and/or builder salts present in thosecompositions.

SUMMARY OF THE INVENTION

In one aspect, the present invention relates to a novel compoundrepresented by the formula: ##STR4## wherein R is an alkyl group havingfrom about 8 to about 18 carbon atoms, and mixtures thereof, n has avalue from 1 to 6, R₁ is selected from the group consisting of an alkylgroup having from 1 to about 12 carbon atoms, H, or ##STR5## wherein thesum of n+m=3 to 12, Z=H or SO₃ M and M=NH₄, Na, or K.

The compounds of the present invention are useful as antimicrobialadditives in cleaning compositions containing a cleaning agent.

This and other aspects of the present invention will become apparentupon reading the following detailed description of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The cleaners made using the novel compounds of the present invention canbe formulated to exhibit desirable characteristics with, regard to bothphysical properties and performance in use. As to physical properties,the composition may be formulated to be homogeneous, pourable, andfree-flowing from the container as manufactured as well as after agingat various temperature. For example, they may be formulated to exhibit ahigh degree of stability upon storage at normal room temperature ofabout 24° C. over a period of many months without any appreciableprecipitation or formation of layers. Also, when subjected to elevatedtemperatures of about 38° C. or cooled to about 5° C., the liquid willremain in homogeneous form. As a result of this homogeneity, even whenonly very small quantities are dispensed, the components will be presentin the correct proportions. Furthermore, the liquid may be packaged inany suitable container such as metal, plastic, or glass bottles, bags,cans or drums.

The liquid compositions of the present invention include as the cleaningagent, a wide selection of surfactants which can be anionic, nonionic orcationic, as well as mixtures or blends of nonionic surfactants witheither anionic surfactants or with cationic surfactants.

Suitable anionic surfactants which may be employed in the cleaningcompositions of the invention include alkylbenzene sulfonates orsulfates, alkyl esters of sulfuric acid or sulfonic acids, alkylethoxysulfates, phosphate esters, sulfosuccinates as well as sulfateesters of alkylphenol polyglycidol ethers.

Nonionic surfactants which may be used as cleaning agents include, forexample, alkyl phenols, oxyalkylated alcohols, oxyalkylated fatty acids,and oxyalkylated amines where the oxyalkyl groups are, for example,oxyethyl or oxypropyl, alkylphenol polyglycidol ethers, and alkylpolysaccharides among others.

Cationic surfactants which may be used as the cleaning agents includefor example, quaternary amine surfactants, alkanolamides, and amineoxides.

Of the three broad types of surfactants employed as cleaning agents onlycationic surfactants are known to have antimicrobial properties andthese appear to be limited to a selected molecular weight range.

Surprisingly, it has been found that antimicrobial properties in thecomposition of the present invention are provided by sulfated aliphaticamine-polyglycidol adducts represented by Formula I hereinabove.

The sulfated amine polyglycidol adducts represented by Formula I arecomprised of a primary or secondary alkyl amine group and the selectednumber of glycidol groups. Suitable alkyl amines include homogeneousamine groups as well as mixtures such as those sold commercially as cocoamines, soya amines, and tallow amines or mixed fatty amines. While thealkyl groups may be branched or linear, where improved biodegradabilityis desired, linear alkyl groups with minimal branching are preferred.

Sulfated amine glycidol adducts represented include those of Formula Iin which R represents, for example, octyl, nonyl, decyl, hendecyl,dodecyl or coco or lauryl, tetradecyl, pentadecyl, hexadecyl,heptadecyl, octadecyl or stearyl (tallow or soya), and mixtures thereof.

Antimicrobial effective amounts of the sulfated amine glycidol compoundsinclude those which inactivate or prevent the growth of organisms suchas bacteria or fungi. In general cleaning formulations, the amineglycidol compound is present in molar ratios to the surfactant presentas the cleaning agent of from about 10:1 to about 1:10, preferably atmolar ratios of from about 7:1 to about 1:9, with molar ratios of fromabout 5:1 to about 1:5 being more preferred. The selection of molarratios of the antimicrobial amine glycidol compound to surfactant isrelated to the application, institutional use, for example, in hospitalsor commercial laundries, may employ compositions having higher molarratios of the antimicrobial compound.

The cleansing composition of the present invention may also includeingredients such as perfumes, colorants, and sequestering or chelatingagents such as ethylenediamine polyacetic acids and their saltsincorporated to improve the cleansing properties of the products in hardwater.

The preferred form of the cleansing compositions of the presentinvention is a liquid in which the solvent is water, a water soluble, ora water miscible compound such as an alcohol, glycol or glycol ether.The antimicrobial composition may also be produced in many differentforms such as dried granules, flakes, etc., which are well known in thecleansing products industry.

The novel antimicrobial sulfated amine polyglycidol adducts of thepresent invention may be used as a preservative in water-basedfunctional fluids as well as in surface coating compositions in whichwater is a major ingredient. In these and other applications, thesulfated amine glycidol compounds are useful in controlling the growthof bacteria and fungi as well as providing surfactant properties withoutadversely affecting the color, pH or other physical properties of thesurface-coating composition. Suitable amounts of the amine polyglycidoladducts used as a preservative include, for example, those in the rangefrom about 0.000001 to about 5% by weight.

EXAMPLES

The following examples serve to give specific illustrations of thepractice of this invention, but they are not intended in any way tolimit the scope of this invention.

EXAMPLE 1 Preparation of a Polyglycidol Sulfated Compound

A one-liter, 3-necked round bottom flask was fitted with a mechanicalstirrer, thermometer, nitrogen inlet, dropping funnel and vent. Under anitrogen atmosphere, Armeen C, 280 g (1.4 m) was placed in the flask andthe contents heated to 150° C. Glycidol, 414.8 g (5.6 m) was placed inthe dropping funnel and glycidol addition to the Armeen C initiated.Reaction temperature was maintained at 143°-150° C. and glycidoladdition was completed in 31/2 hours. The flask and its contents werecooled and the product removed. The product, a 4-mole glycidol adduct of95% C₁₂ aliphatic amine weighed 694 g.

In a 500 ml round-bottom flask was placed 49.6 g (0.1 m) of the ArmeenC-4 mole glycidol adduct. The flask was fitted with a mechanicalstirrer, thermometer, nitrogen inlet and vent. Under a nitrogenatmosphere, the contents of the flask were heated to 120° C. Sulfamicacid 10.7 g (0.11 m) was added to the contents of the flask in fourincrements over a 2 hour period at 112°-120° C. The reaction mixture wascooled and monoethanolamine, 1.7 g (0.27 m) and 12.8 g ethanol addedwith stirring. The product, Armeen C-glycidol (4)-sulfate, ammonium saltweighed 74 g (80% active).

EXAMPLE 2 Preparation of Another Polyglycidol Sulfated Compound

The procedure of Example 1 was reported in a similar manner. Conditionswere as follows:

Preparation of Armeed C-3 mole glycidol adduct:

    ______________________________________                                        Armeen C          380      g (1.9 moles)                                      Glycidol          422      g (5.7 moles)                                      Reaction temperature                                                                            146-155°                                                                        C.                                                 Reaction time     31/2     hours                                              Product weight    800      g                                                  ______________________________________                                    

Preparation of the sulfate derivative:

    ______________________________________                                        Armeen C-3 mole glycidol adduct                                                                     42     g (0.1 mole)                                     Sulfamic acid         19.4   g (0.2 mole)                                     Monoethanolamine      1.7    g (0.1 mole)                                     Ethanol               12.9   g                                                Toluene (as solvent)  200    ml                                               Reaction temperature  110°                                                                          C.                                               Reaction time         6      hours                                            Product weight        61     g                                                ______________________________________                                    

Properties

The surface tensions (ASTM Designator D1331-56) of the products at 0.1wt.% concentration were as follows:

    ______________________________________                                        Product of Example 1                                                                             30       dynes/cm                                          Product of Example 2                                                                             33       dynes/cm                                          ______________________________________                                    

The surface tension of distilled water is approximately 72 dynes/cm.

The product from Example 1 was soluble in 50% sodium hydroxide solutionand the product from Example 2 was soluble in 40% sodium hydroxidesolution.

Antimicrobial Evaluation

Minimum Inhibitory Concentration (MIC's) were determined and compared toa nonylphenol-glycidol based surfactant. The results are shown inattached Table I. MIC tests indicate that these adducts possesssignificant antimicrobial and antifungal activity.

                  TABLE I                                                         ______________________________________                                        Minimum Inhibitory Concentration (PPM)                                        COMPOUND OF                                                                                    STAPHYLO-                                                    ESCHERIDIDA      COCCUS      ASPERGILLUS                                      COLI             AUREUS      NIGER                                            (Gram Negative)  (Gram positive)                                                                           (Fungus)                                         ______________________________________                                        Example I                                                                             64           32          512                                          Example II                                                                            64           32          512                                          Nonyl-  >25,000      >25,000     >25,000                                      phenol-                                                                       glycidol                                                                      ______________________________________                                    

SURFACE ACTIVE PROPERTIES

Surface and interfacial tensions (ASTM designation D1331-56) on each ofthe sulfated amine glycidol compounds were determined and listed inTable II. The surface tension of distilled water is approximately 72dynes/cm.

While the invention has been described above with reference to specificembodiments thereof, it is apparent that many changes, modifications,and variations can be made without departing from the inventive conceptdisclosed herein. Accordingly, it is intended to embrace all suchchanges, modifications, and variations that fall within the spirit andbroad scope of the appended claims. All patent applications, patents,and other publications cited herein are incorporated by reference intheir entirety.

What is claimed is:
 1. An antimicrobial composition for use incontrolling bacteria and fungi in an aqueous medium comprising acompound represented by the formula: ##STR6## wherein R is an alkylgroup having from about 8 to about 18 carbon atoms, and mixturesthereof, n has a value from 1 to 6, R¹ is selected from the groupconsisting of an alkyl group having from 1 to about 12 carbon atoms andH, and M is NH₄, Na, or K.
 2. The antimicrobial composition of claim 1in which R represents decyl.
 3. The antimicrobial composition of claim 1in which R represents dodecyl.
 4. The antimicrobial composition of claim1 in which R represents tetradecyl.
 5. The antimicrobial composition ofclaim 1 in which R represents coco.
 6. The antimicrobial composition ofclaim 1 wherein said antimicrobial compound is present in saidcomposition in a molar ratio of between about 10:1 and about 1:10relative to the molar ratio of said cleaning agent employed.
 7. Anantimicrobial compositions for use in controlling bacteria and fungi inan aqueous medium comprising a cleaning agent and an antimicrobialcompound represented by the formula: ##STR7## wherein R is an alkylgroup having from about 8 to about 18 carbon atoms, and mixturesthereof, n has a value from 1 to 6, R¹ represents an alkyl group havingfrom 1 to about 4 carbon atoms and M=NH₄, Na, or K.